In the phenothiazine field, many products have been demonstrated, especially for their activity with respect to the central nervous system, in particular amides derived from phenothiazine, of general formula: ##STR3## in which R is, in particular, a hydrogen atom, have been described in U.S. Pat. No. 3,112,310. Thioamides derived from phenothiazine, of general formula: ##STR4## in which A is a carbon-containing chain and Z is, in particular, a dialkylamino radical or a nitrogenous heterocycle, have also been described in Belgian Patent No. 612,885.